Introduction to Bolt and Screw Fasteners
Introduction to Bolt and Screw Fasteners
1Chamfered End
The tapered or beveled end of the screw that helps it enter and thread smoothly into the material or mating part (e.g., a nut).
2
Thread Length
Thread Length
The portion of the screw that is threaded. For fully threaded screws, it is measured from under the head to the tip.
3
Thread
Thread
The helical shape around the shank. It converts rotational motion into linear motion to drive the screw into the material.
4
Run Out
Run Out
The transition point where the thread ends and meets the unthreaded shank.
5
Grip Length
Grip Length
The unthreaded portion of the screw (usually from under the head to the start of the thread). It determines how well the screw clamps the joint.
6
Body Shank
Body Shank
The main cylindrical body between the head and the threads, usually smooth to provide structural support.
7
Fillet Radius
Fillet Radius
The curved transition between the head and the shank, designed to reduce stress concentration.
8
Bearing Surface
Bearing Surface
The underside of the head that contacts the mating part. It distributes the load and provides clamping force.
9
Across Flat
Across Flat
The distance between two opposite flat surfaces of a hexagonal head, used for wrench sizing.
10
Head
Head
The top part of the screw that provides a surface for applying torque during installation or removal.
The above technical information is for reference only.